What is responsive neurostimulation?

Responsive neurostimulation is a new approach to treating medically uncontrolled partial onset seizures. The RNS® System is the first device to provide responsive neurostimulation, automatically monitoring brain signals and providing stimulation to abnormal electrical events just when it is needed. The system is approved by the U.S. Food and Drug Administration (FDA) as an adjunctive treatment for adults with medically refractory partial seizures that come from one or two seizure targets identified by your doctor.

The RNS Neurostimulator is placed under the scalp and within the skull by a surgeon. One or two leads are then placed at the seizure target and connected to the neurostimulator. After the scalp heals, the neurostimulator should not be noticeable to others. The neurostimulator continuously monitors the brain’s activity and is programmed by the epilepsy doctor to detect and record specific patterns that could lead to a seizure. When these patterns are detected, the neurostimulator responds with brief pulses of stimulation intended to disrupt the abnormal brain activity before a seizure occurs. Detection and stimulation settings are individualized for each patient’s patterns and so that stimulation is not felt. In addition, each patient gets a take-home monitor so that brain activity data can be sent to the epilepsy doctor between office visits.

Who can get this procedure?

The RNS® System is approved as an adjunctive therapy for adults (18 years or older) with partial onset epilepsy whose frequent, disabling seizures have not been controlled by at least two different medications and have one or two seizure onset zones.

How is the surgical procedure performed?

The neurostimulator and leads are placed under general anesthesia by a neurosurgeon trained in the procedure. Generally, the patient will stay in the hospital one or two days and then return to normal activities.

What is the outlook?

Although not a cure for epilepsy, treatment with the RNS® System reduces seizures in most patients. Prospective clinical trials have demonstrated median seizure frequency reductions of 44% at one year, 53% at two years, and seizure reductions ranging from 60 to 66% three to six years post-implant.

Resources

The RNS® System is manufactured by NeuroPace, Inc. Additional information for patients and physicians is available at their website, neuropace.com (http://www.neuropace.com).